<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta http-equiv="X-UA-Compatible" content="IE=edge" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>优惠价格</title>
    <style>
      .box {
        width: 150px;
        height: 50px;
        border: 2px solid red;
        font-size: 25px;
        text-align: center;
        line-height: 50px;
        font-family: 微软雅黑;
      }

      .left {
        float: left;
        background-color: red;
        color: #fff;
        font-weight: bolder;
      }

      .right {
        position: relative;
        float: left;
        background-color: #fff;
        color: #a5a5a5;
        font-size: 23px;
        text-decoration: line-through;
      }

      .right .triangle {
        position: absolute;
        top: 0;
        border-style: solid;
        border-width: 0 20px 50px 20px;
        border-color: transparent transparent transparent red;
      }
    </style>
  </head>
  <body>
    <div class="box left">&yen; 2099.00</div>
    <div class="box right">
      &yen; 2649.00
      <div class="triangle"></div>
    </div>
  </body>
</html>
